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Testing the power transistor and installing new CAS

I was wondering if there is any way to test the power transistor on our cars with a voltmeter. I know what it looks like but I am not so sure of where it is located I think I remember seeing it on the passenger side fender wall toward the back but I could be wrong. If anyone could let me know where its located that would help a lot. As far as testing it I would assume you want 12V going in but it is my understanding that this acts as an amplifier of some sort. Anyone know what kind of voltage and amperage I should be getting out of it? Another question I have regards installing a new CAS. Can I just remove the old one and put the new one on or do I have do mess with cam positioning and timing and that sort of thing? I would appreciate any input you guys have on this. Once I get this done my car should be running again so I can get it all winterized and put away until I can drive again in a couple months, thanks.
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Alright then I was way off as far as the location. Anyone have any input on how to install a new CAS. I would really appreciate the info. I don't want to mess up my timing.


Well-known member
Aug 30, 2004
West Simsbury, CT
There's a detailed set of tests in the FSM for the power transistor. They were too complicated for me, so I just replaced the entire unit. It didn't fix my code 44, which still plagues the car every now and then on the freeway /ubbthreads/images//graemlins/frown.gif

You'll have to reset your timing when the new CAS goes in. Be sure to orient the new CAS correctly. There's a mark on one end of the the thing that spins, which coincides with a mark on the end of the camshaft. Otherwise your ECU will think the timing is 180* the opposite.

Alright, if I can't get it started after I replace the CAS I'll just pick up a new power transistor. This looks like a pretty expensive part though. I just checked autozone and its running like $150. How do I go about resetting the timing?
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